Periodic Table: Bell Ringer What does a period and a group refer to on the periodic table? What period and group is Bromine on? What element is on period 5 and group 10? For homework, how did you classify the elements on the periodic table?

Periodic Table

Metallic Properties

Non-metallic Properties

History of the Periodic Table Dmitri Mendeleev: Russian chemists and teacher When organized elements into groups by similar chemical properties, he observed the periods increasing in atomic mass. His organization system was successful at predicting undiscovered elements. Do you observe any inconsistencies with his organization system?

History of Periodic Table Henry Moseley: British Physicists Observed that when elements were placed in groups by chemical properties, the periods consistently increased by atomic number. Currently accepted organization system for elements.

Bell Ringer: Periodic Table 1. How is the current periodic table arranged? 2. Classify the following properties as metallic or non- metallic. a. ductile b. low density c. high luster d. insulator 3. What element is on period 3; group 16? 4. Circle the elements below that have similar chemical properties: Carbon (C); Nitrogen (N); Silicon (Si); Boron (B)

Organization of Periodic Table Why do elements in the same group have similar chemical properties?

Valence Electrons Electrons in the highest energy level of an element’s atom. Calculate using short-hand electron configuration. Determines the chemical reactivity of an element.

Periodic Table : Bell Ringer 1. a. What period and group is Aluminum on? b. What element is in period 4; group 2 ? 2. Circle the elements below that have similar chemical properties. Carbon (C), Nitrogen, (N), Silicon (Si), Boron (B) 3. What are valence electrons? 4. Why is it important to know the number of valence electrons an element can have?

Short-Hand Electron Configuration Short -hand configuration targets valence electrons Ex. Sulfur (S): [ Ne] 2s22p4 = 6 valence electrons

Valence Electrons Worksheet Key 1. 7 ve- 11. 1ve- 2. 5ve- 12. 2ve- 3. 2ve- 13. 4ve- 4. 5ve- 14. 7ve- 5. 2ve- 15. 6ve- 6. 8ve- 16. 2ve- 7. 1ve- 17. 3ve- 8. 2ve- 18. 1ve- 9. 2ve- 19. 8ve- 10. 6ve- 20. 2ve-

Organization of Periodic Table Why do elements in the same group have similar chemical properties?

Periodic Table Lab: Valence Electrons grps grp 1 ve- grp 2 grp 3-12 grp 13 ve- grp 14 grp 15 grp 16 grp17 grp18 A B C D What can be concluded from the data table?

Periodic Table: Valence Electrons Lab grps grp 1 ve- grp 2 grp 3-12 grp 13 ve- grp 14 grp 15 grp 16 grp17 grp18 A 1 2 3 4 5 6 7 8 B C D What can be concluded from the data table?

Common Periodic Table Groups Periodic Groups Group # Valence Electrons Chemical Properties Alkali Metals 1 1 ve- Highly Reactive metals Only needs to lose 1 ve- to reach STABILITY. Depends on lower energy level that is filled. Alkaline-Earth Metals 2 2ve- Reactive Only needs to lose 2 ve- to reach STABILITY. Depends on lower energy level that is filled. Transitional Metals 3-12 Varies in amount of valence electrons lost to reach STABILITY. Halogens 17 Highly Reactive non-metals. Only needs to gain 1 ve- to reach STABILITY. Depends on filling up outer energy level. Noble Gases 18 Inert non-metal gases. Not reactive elements. Very STABLE elements because outermost energy level is filled, 8ve. Exception: 2 ve for He.

Chemical Stability Metals: Will lose ve- to reach stability. Form cations (+ charged atoms) Non-metals: Will gain ve- to reach stability. Form anions (- charged atoms)

Chemical Stability Determine what type of ion each element below would form to reach maximum stability. a. Sodium Na1+ b. Oxygen O2- c. Argon Ar d. Phosphorus P3- e. Chromium Cr2+

Bell Ringer: Chemical Stability Write down what comes to mind when you think about chemical stability for elements. 2. Label your periodic table with the following groups: Alkali metals (Group 1) Alkaline earth metals (Group 2) Halogens (Group 17) Noble gases (Group 18) Transitional metals (Group 3-12)

Periodic Table and Groups

Ions and Chemical Stability Lab In pairs, look at 16 different elements and answer the following questions: Metal or non-metal Neutral, anion, or cation. Symbol and specific charge if needed. *neutral if element is naturally stable (noble gas) *anion: non-metal not naturally stable *cation: metals

Size of an Ion Use the diagram below to determine what happens to the size of an atom when it becomes an ion.

Size of a Cation A cation is smaller than its parent atom. Why? Because metals will lose an energy level in the process of becoming a cation.

Size of a Cation

Size of an Anion

Size of an Anion A anion is larger than its parent isotope. Why? Repulsion force increases as more electrons are added to the outer most energy level. Swells the energy level.

Size of an Anion

Size of Ions Circle the atom that is larger in size. Ca or Ca2+ S or S2- Circle the atom that is smaller in size. a. Al or Al3+ b. N or N 3-

Bell Ringer: Chemical Stability a. Most stable group on periodic table? Explain. b. Most reactive metallic group? Explain. c. Most reactive non-metallic group? Explain. 2. Predict what type of ion each element below would form to reach maximum stability. a. Cesium b. Selenium c. Helium 3. Identify which atom is larger in each example below. a. Al or Al3+ b. Br or Br 1-

Periodic Trends

Periodic Properties and Trends Atomic Radius: -Size of an atom. Distance from nucleus to highest energy level for that atom. (picometers, pm). Ionization Energy: Energy required to remove an electron from an atom. Energy required to form a cation.

Periodic Trends: Atomic Radius

Periodic Trends: Atomic Radius Across a Period Down a Group

Periodic Trends: Ionization Energy

Periodic Trends: Ionization Energy Across a Period: Down a Group:

Exit Slip Use your graph on atomic radius and ionization energy answer these questions: Rank the following elements from largest to smallest in size. Explain your results. Ar, Mg, S Al Rank the following elements from smallest to largest in ionization energy. Explain your results. Ne, Ar, He

Periodic Table Transitional Elements: short groups. Representative Elements: tall groups . Transitional Elements: short groups.

Hydrogen Lab